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#include <iostream>
#include <string>

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    string a, b, c;
    if (!(cin >> a >> b >> c)) return 0;

    int n = a.length();
    long long total_pairs = 0;
    long long cnt0 = 0;
    long long cnt_m1 = 0;

    for (int j = 0; j < n; ++j) {
        int d = (a[j] - '0') + (b[j] - '0') - (c[j] - '0');
        
        long long next_cnt0 = 0;
        long long next_cnt_m1 = 0;

        if (d == 0) {
            next_cnt0 = cnt0 + 1;
        } else if (d == -1) {
            next_cnt_m1 = cnt0 + 1;
        }

        if (d == 10) {
            next_cnt0 += cnt_m1;
        } else if (d == 9) {
            next_cnt_m1 += cnt_m1;
        }

        cnt0 = next_cnt0;
        cnt_m1 = next_cnt_m1;

        total_pairs += cnt0;
    }

    cout << total_pairs << "\n";

    return 0;
}